Once installed, the Sentry needs to be set up to trigger at the right level. This can be done scientifically, using a sound level meter, or it can be set up by ear - when the music can be heard at the boundary, it is too loud.
The Sentry has two trigger levels. For many applications one is adequate, but if you want to be able to easily switch to a different level for any reason then this is possible. An indicator on the front panel shows which threshold is currently selected. A remote key switch and automatic timer are available to select the threshold. See the Options page for more details.
The controls for adjusting the threshold are behind the front cover. The front cover must first be removed and then a screwdriver is used to make the adjustments. This should only need doing once, after the Sentry is first installed.
The Sentry is capable of using the standard "A" or "C" weighting, Linear response or a special Bass weighting. Although most noise measurement is carried out using "A" weighting, for entertainment noise control the Sentry should usually be used on the "C" or Linear setting. The reason is that most music noise problems are in the low frequencies, which are removed by the "A" weighting filter.
The period of time that the sound level is allowed to be over the limit before the power is cut can be set from 10 seconds to 70 seconds. This adjustment is also hidden behind the removable front cover.
For most applications the internal microphone is adequate. An external microphone is available as an option. An external microphone is connected via a three-way terminal strip behind the front cover. More details...
The Sentry has provision for a security loop. This can be used to detect when doors or windows are opened, as this would impair the sound proofing of the venue.
Magnetically operated reed switches can be used for this purpose. When connected windows or doors are opened the music is cut.
The best way to avoid tampering is to mount the Sentry out of reach. However, this is not always possible so security screws can be provided instead of the standard ones for the front panel.
An indicator on the front of the Sentry shows if the microphone as been damaged or tampered with. An optional external mic. tamper indicator is available.
For more detailed information about installation and wiring of the Sentry please visit our Technical Support web site.
Sentry Music Noise Controller and its optional parts.